Since Fusion is so critical to Gem-Knights' strategy, pay careful attention to which cards you include in your Extra Deck, and remember to keep space in your Main Deck for Gem-Knight Fusion
You can get the difficulty modes from someone who already has them unlocked, but if you don't know anyone else like that, you're out of luck
Black has a few ways to accomplish this, though some are colorless artifacts or lands that any color can use: Defense Grid This artifact increases the cost of spells cast during your turn by three colorless mana
The cards will be available in various sets, spanning Play Booster Box, Collector Booster Box, Starter Kit, Pre-Release Pack as well as regular and gift bundles
For instance, something like wildfire could be played on animals that live in the forest, and cause that card to be removed from the game